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121.
Praemachiloides iberica n. sp. is described and compared with the other four known species of the genus: P. janetschecki, P. insularis, P.tarsispina and P. autumnalis. The main difference of P. iberica n. sp. from the other known congenerics is the presence, in the male, of a field of plaited setae on the ventral surface of the maxillary palp.  相似文献   
122.
Journal of Plant Diseases and Protection - Pythium aphanidermatum is the most wide-spread root pathogen in greenhouse cucumber. Although environmental condi-tions are known to affect the disease...  相似文献   
123.
Ground and surface water contamination by herbicides applied to olive groves in Spain and other Mediterranean countries is demanding strategies to prevent and remediate the environmental problems repeatedly caused by such herbicides. In this study, six different organic cations (L-carnitine, spermine, hexadimethrine, tyramine, phenyltrimethylammonium, and hexadecyltrimethylammonium) were incorporated into Na-rich Wyoming montmorillonite (SWy-2) and Ca-rich Arizona montmorillonite (SAz-1) at two different loadings (50% and 100% of the cation exchange capacity of the clays) as a strategy to enhance the affinity of the clay minerals for three herbicides widely used in olive groves: terbuthylazine, diuron, and MCPA. The modified montmorillonites were characterized and tested as adsorbents of the herbicides through batch adsorption tests. At the experimental conditions used, some of the modified montmorillonites removed more than 95% of the herbicide initially present in aqueous solution, whereas the unmodified clays removed less than 15%. All three herbicides displayed very strong affinities for SAz-1 exchanged with hexadecyltrimethylammonium cations, particularly when these were incorporated at 100% of the cation exchange capacity of the clay mineral. Terbuthylazine and diuron also displayed very strong affinities for SWy-2 exchanged with L-carnitine and spermine, respectively. The chemical characteristics of the organic cation greatly influenced the adsorptive properties of the resultant organoclay. The herbicides were in general reversibly adsorbed by the modified clays. The results indicate that some of the tested modified clays could be suitable for the removal of the assayed herbicides from contaminated water and also as possible supports for the design of slow release formulations of such herbicides to attenuate their environmental impact when used in high-risk scenarios such as olive groves.  相似文献   
124.
Shiga toxin-producing Escherichia coli (STEC) O128:H2 is recognised worldwide to be an important non-O157 STEC associated with human illness and in particular with causing haemolytic uraemic syndrome. This serotype is commonly isolated from sheep and is being increasingly isolated from deer. We determined the virulence profile and genetic relationships of one human, six sheep and five deer intimin-negative STEC O128:H2 strains isolated in Spain over a 7-year period. Our goals were to establish the presence of other virulence-associated factors, such as SubAB, in intimin-negative STEC O128:H2 strains involved in human disease and in that case, to determine if sheep and/or deer represent a reservoir of SubAB-positive STEC O128:H2. All the strains lacked the eae gene and carried subtilase cytotoxin (SubAB) encoding genes (subAB) and tia genes, but not saa gene, suggesting the presence of the recently identified new variant of SubAB, encoded on a putative pathogenicity island together with tia. We report for the first time the presence of subtilase cytotoxin encoding genes in intimin-negative STEC O128:H2 strains pathogenic for humans and how this finding might explain their clinical relevance despite neither carrying eae nor stx subtypes associated with severe clinical outcomes, but only stx1c and stx2b. Multilocus sequence typing analysis revealed that STEC O128:H2 strains from sheep and deer belong to the clonal lineage of STEC O128:H2 strains involved in diarrhoeal and haemorrhagic diseases in humans. Our results indicate that sheep and deer represent a reservoir of SubAB-positive STEC O128:H2 strains and thus a potential source of human infection.  相似文献   
125.
The investigations were carried out with 484 sows from two farms (farm A: housing the sows in small groups of 8 animals each, farm B with a large group of 100 sows) and a total number of 982 inseminations. The number of agonistic interactions was registered for each sow during 48 h after mixing soon after weaning the piglets at farm A. The individual rank place in the social hierarchy was calculated on the basis of wins and defeats and the sows were divided in high and low ranking sows. At farm B the rank position was estimated on the basis of the daily feeding order at two electronic feeding stations (first half of the sows in the feeding order = high ranking, second half = low ranking). Additionally, the following parameters were recorded for each sow: parity, genotype, farrowing rate and litter size (total and alive born piglets). The analysis showed that sows with a high rank position had a significantly higher farrowing rate (88.8%) compared to group-mates with low rank places (82.8%, p = 0.051) (farm A). Sows with a high rank position reached a significantly higher litter size of total born piglets (12.66, 16.14 piglets per litter respectively) than the low-ranking group-mates (12.13, 14.83 piglets/litter respectively — farms A and B). When mixing sows, the time and the conditions (e.g. group size, space allowance per sow) have to be considered to prevent the negative influence of low rank order on fertility.  相似文献   
126.
Real-time PCR was used to detect and quantify Verticillium dahliae and to assess the susceptibility of four Capsicum annuum cultivars (Luesia, Padrón, SCM331 and PI201234) and the Capsicum chinense cv. C118 to this pathogen. The symptoms which developed after infection included stunting and yellowing, and were more acute in the cv. SCM331, which also suffered defoliation in later stages of the disease and in C118, which suffered severe stunting. Quantification of the pathogen DNA in roots 23 and 34 days post-inoculation (dpi) revealed that there were significantly higher amounts of Verticillium dahliae DNA in C118 than in the other cultivars, followed by SCM331, Padrón and PI201234. The lowest amounts of fungal DNA in roots were found in Luesia. In hypocotyls, the highest amounts of fungal DNA were found in SCM331, while Luesia, Padrón and PI201234 had much lower amounts, and C118 had intermediate levels. When a compatible versus an incompatible system was studied, using the near-isogenic tomato lines LA3030 (susceptible) and LA3038 (resistant to V. dahliae), we were able to detect fungal DNA in both lines. As expected, the fungus/plant DNA ratio was lower in LA3038 than in LA3030 and it decreased with time in LA3038. The amount of Verticillium dahliae DNA in the roots of LA3030 remained constant between days 23 and 34 post-inoculation, but increased 10-fold in collars. Finally, when real-time PCR was applied as a diagnostic method to samples from pepper plants, soil and water collected from farms in northwest Spain, we were able to detect V. dahliae DNA in these samples even when symptoms of the disease were not evident.  相似文献   
127.
Fishery by-products are rich in biologically active substances and the use of green and efficient extraction methods to recover these high-added-value compounds is of particular importance. In this study, head, skin and viscera of rainbow trout and sole were used as the target matrices and accelerated solvent extraction (ASE) (45–55 °C, 15 min, pH 5.2–6.8, 103.4 bars) and pulsed electric fields (PEF) (1–3 kV/cm, 123–300 kJ/kg, 15–24 h) were applied as extraction technologies. The results showed that ASE and PEF significantly increased the protein extract efficiency of the fish by-products (p < 0.05) by up to 80%. SDS-PAGE results showed that ASE and PEF treatments changed the molecular size distribution of the protein in the extracts, which was specifically expressed as the change in the area or number of bands between 5 and 250 kDa. The antioxidant capacity of the extracts was evaluated by oxygen radical absorbance capacity (ORAC) and total antioxidant capacity (ABTS) assays. The results showed that both ASE and PEF treatments significantly increased the antioxidant capacity of rainbow trout and sole skin and head extracts (p < 0.05). ASE and PEF extraction processes can be used as new technologies to extract high-added-value compounds from fish by-products.  相似文献   
128.
The distribution of viral genome in the tissues of juvenile European seabass (Dicentrarchus labrax) during the course of a Red Spotted Grouper Nervous Necrosis Virus (RGNNV) infection has not yet been described. The present study addresses this and indicates which target organs may be involved in viral replication. This information should enable more accurate detection of virus in asymptomatic carriers, and in turn help to control the spread of the disease. The aim of this study was to examine the pattern of expression of viral genomic segments RNA1 and RNA2, using two absolute real-time PCRs (RT-qPCR), over the course of a RGNNV infection after administering the virus by intramuscular injection. In situ hybridization was also used to locate the RNA2 viral segment in different organs throughout the infection. The experimental challenge provoked an acute form of viral nervous necrosis (VNN), with a resulting cumulative mortality of 37%. The RT-qPCRs designed allowed the detection of both genomic segments in all the organs tested (nervous and non-nervous tissues) at all sampling times examined. The highest viral RNA copy number was found in eyes, although viral replication appeared to begin in the brain. Viral replication was also recorded in pooled internal organs and in caudal fin. However, the increase in the viral RNA copy number in these organs did not result in an increased viral titre, which may indicate that a productive infection does not take place in non-nervous tissues, possibly due to a failure in a viral post-replication step.  相似文献   
129.
Summary

Optimal rooting conditions have been determined for shoot cultures of Camellia japonica cv. Alba Plena derived from a 50 year old tree: dipping the base of shoots in 1 g l?l solution for 15 min, followed by 12 days’ darkness, induced 87% rooting in shoots cultured with Woody Plant Medium (WPM) macronutrients. Halving the auxin concentration or exposure time considerably reduced this rate, and root formation was severely inhibited if an initial dark period for the entire shoot was not used. The type of support (agar or paper bridges) did not significantly affect the rooting percentage or number of roots per rooted shoot, but liquid media induced greater root elongation. No significant differences were observed between the use of WPM and a modified Heller’s medium as regards the rooting percentages achieved, but the number of roots formed was considerably greater with WPM, as was the survival rate after transfer to soil (70% for transfer as against 35% with the modified Heller’s medium). Best survival rates were achieved when shoots were transferred to the acclimatization soil 12 days after auxin treatment, i.e. immediately after the dark period.  相似文献   
130.
This paper focuses on the analysis of the slope and catchment erosion dynamics in a typical Mediterranean context and its sensitivity to recent climatic and socio‐economic changes. The main objective of the present study is to test the reliability of digital photogrammetric analysis to evaluate the time and space evolution of erosion processes mainly triggered by surface running waters and landslides for about the last 60 years. The selected test area is the Landola catchment, a minor tributary of the Upper Orcia River Valley (Southern Tuscany). The Upper Orcia valley is a key site for the comprehension of denudation processes typically acting in Mediterranean badland areas thanks to the following: (i) the availability of long‐lasting erosion monitoring datasets (20 years' long direct measurements at erosion ‘hot spots’); (ii) its representativeness as a sub‐humid Mediterranean badland area; and (iii) the rapidity of development of erosion processes, which makes it suitable as an open‐air laboratory for the study of badland dynamics. The outputs of this work highlight that the application of high‐resolution digital photogrammetric methodologies can represent a powerful and low‐cost tool to evaluate rates and spatial–temporal distribution of denudation processes, as confirmed by the validation through field point monitoring in areas close to the study area. The results obtained for the study area confirm that high erosion rates are a persistent environmental problem for the Upper Orcia Valley, which is not solved up to now, despite various land conservation interventions. The performed multi‐temporal analysis shows a slight decrease in the average water erosion rate during the last 60 years and a parallel increase in the frequency of mass wasting events. These variations are most likely related to a complex interplay between land use changes that have affected the study area during the studied period, revealing a very delicate equilibrium between farming activities and erosion processes. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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